Plate Area Calculation
Projected vs. Actual Area
Only the horizontal projection of an inclined plate contributes to settling. This distinction is at the heart of every plate area calculation.
Plate Area Calculation
The actual surface area of a plate is simply length × width. But because the plate is inclined, only its horizontal projection — length × width × cos(θ) — counts as effective settling area.
Summing the projected area of every plate gives the total projected settling area used in A = Q / SLR. This is why plate count, not just plate size, determines capacity.
Understanding projected area also explains the footprint advantage: dozens of plates stacked in a small vessel deliver the projected area of a conventional tank many times larger.
A_actual = L × WPhysical plate surface area.
A_projected = L × W × cos(θ)Effective (horizontal) settling area per plate.
A_total = N × A_projectedTotal projected area for the pack.
Projection Factors
Free Sizing Check
Try the interactive Plate Settler Sizing Calculator, or send us your flow and water-quality data for a preliminary sizing at no cost.
Key Considerations
Projection Matters
Use projected, not actual, area in all capacity calculations.
More Plates
Capacity scales with plate count at fixed geometry.
Compact Footprint
Stacked plates deliver large projected area in a small vessel.
Related Pages
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